Anoxic/Ischemic Injury: If the neuron is deprived of oxygen or glucose for more than 5 to 7 minutes, it dies. This is manifest as the cytoplasm becoming pink and homogeneous (eosinophilic) and the nucleus becoming dark and shrunken (pyknotic), with eventually the cell disappearing entirely. http://www.uvm.edu/~jkessler/NP/neuropbr.htm
Cranford referred to Terri's "anoxic/ischemic" trauma. Loss of oxygen ("anoxic") causes the neuron to die.
I thought she had a 10 minute loss of circulation from a heart attack, causing the anoxia.
I think it was an ischemic event --- I would still question whether her skull is really a fluid filled cavity as that doctor said. I would guess that some or many neurons did die and portions of her brain could be atrophied. Many circuits could be shut off forever. I would never think she could ever be "good as new" or anything close. But maybe her family isn't wrong about her having some cognitive response.